792 mb. g. a. bottlengee on the fishes [nov. 15, 



4. Marcusenius. 



Fetrocejihalus, part., Marcusen, Bull. Ac. St. Petersb. xii. 1854, 

 p. 14, and Mem. Ac. St. Petersb. (7) vii. 1864, no. 4, p. 113. 



Marcusenius, Gill, Proc. Ac. Philad. 1862, p. 129 (1863); 

 Bouleng. Ann. Mus. Congo, Zool. i. 1898, p. 2. 



Heteromormyrus, Steind. Verb, zool.-bot. Ges. Wien, xvi. 1866, 

 p. 765. 



Teetb in the jaws small, truncate or notched, few (3-9 in tbe 

 upper jaw, 4-10 in the lower) ; minute conical teeth on the para- 

 sphenoid and on the tongue ; mouth inferior or subinferior, below 

 tlae level of tbe eyes. Nostrils widely separated. Body short or 

 moderately elongate ; ventrals midway between pectorals and anal, 

 or nearer tbe former. Dorsal and anal subequal in length, or 

 either the longer. Vertebra 41-46 (9-12+4-5 + 27-30). 



Synopsis of the Species. 



I. Anal originating before dorsal. 



A. Caudal peduncle 4 to 5 times as long as deep. 

 D. 22-24 ; A. 30-31 ; L. 1. 62 ; 12 scales round caudal 



peduncle 1. marchii Sauv. 



B. Caudal peduncle 2 to 3 times as long as deep, 



surrounded by 12 scales. 



D. 20; A. 25-26; L. 1. 67 2. sphecodesQ&wf. 



D. 15-18; A. 25-30; L. 1. 58-64 3. bracht/histius Q:\\\. 



D. 18; A. 22; L. 1. 55 4. UngsleycB Grthr. 



D. 20-21 ; A. 27-28 ; L. 1. 46-50 ; caudal peduncle 



3 times as long as deep 5. adspeisus Qihr. 



D. 20 ; A. 28 ; L. 1. 48 ; caudal peduncle twice as 



long as deep 6. Ihuysii^t^. 



C. Caudal peduncle 1^ as long as deep, ^ length 



of head. 

 D. 18 ; A. 23 ; L. 1. 70 ; about 20 scales round caudal 

 peduncle 7. pauciradiatus Stdr . 



II. Dorsal originating before anal. 



A. Caudal peduncle 4 times as long as deep. 



D. 35 ; A. 30 ; L. 1. 55 ; 16 scales round caudal 

 peduncle B. playhstoma Blgr. 



B. Caudal peduncle 2 to 3 times as long as deep. 

 D. 38-40 ; A. 25-27 ; L. 1. 61-68 ; 12 scales round 



caudal peduncle, which is 3 times as long as deep... 9. wilverthi Blgr. 

 D. 30-36 ; A. 23-27 ; L. 1. 65-70 ; 14 scales round 



caudal peduncle, which is twice as long as deep ... 10. discorhynchus Ptrs. 

 D. 35-36; A. 26; L. 1. 65-60; 12 scales round 



caudal peduncle, which is 24 as long as deep 11. petherici Blgr. 



D. 33 ; A. 23 ; L. 1. 60 ; 12 scales round caudal 



peduncle, which is 3 times as long as deep 12. psittacus Blgr. 



D. 17-22 ; A. 20-24 ; L. 1. 53-60 ; 16 scales round 



caudal peduncle 13. isidori 0. & V. 



1. Makcusenius marchii. 



PetrocepJialus marchei, Sauvage, Bull. Soc. Philom. (7) iii. 1878, 

 p. 100. 



