MOEMTEID.E. 157 



8 a. PETROCEPHALUS PIAULLEVILLII. 

 Bouleng. Ann. Mus. Congo, Zool. ii. 3, p. 5, pi. xvii. fig. 1 (1912). 



Depth of body 3 to 3J times in total length, length of head 3§ to i\ 

 times. Head as long as deep ; snout rounded, strongly projecting 

 beyond mouth, as long as eye, which is 4 to 5 times in length of head, 

 and nearly ^ interorbital width ; width of mouth three times in length 

 of head; teeth bicuspid, 11 to 14 in upper jaw, 16 to 18 in lower; 

 nostril near lower border of eye. Dorsal 18-20, about ^ as long as its 

 distance from head. Anal 27-29, originating well in advance of dorsal. 

 Pectoral pointed, a little shorter than head, extending beyond base of 



rig. 105. 



f^ '• f ■'"$1. 



Petrocejplialus hauUevillii. -g-. 

 Type. (A. M. C.) 



ventral. Caudal scaled at the base, with pointed lobes. Caudal 

 peduncle 3 times as long as deep, nearly as long as head. 32-35 scales 

 in lateral line, j^^ '^^ transverse series on body, ^ between dorsal and 

 anal, 12 round caudal peduncle. Silvery, speckled with black, the 

 specks more crowded on the head and back ; dorsal and anal whitish, 

 brown anteriorly. 



Total length 70 millim. 



Chiloango River, Lower Congo. 

 1-3. Types. Chiloango R. at Mayili. Dr. W. J. Ansorge (C). 



4-6. Types. Luculla R., Chiloango. „ 



7-8. Types. Luali R., „ ;> 



Distinguished from P. stuUmaimi by fewer teeth and a more slender 

 and longer caudal peduncle. 



3. ISICHTHYS, Gill. 



1. ISICHTHYS HENRYI, Gill. 

 Add .— 

 12-13. Hgi-. N. Sherbo district, Sierra Leone. N. \\. Thomas, Esq. (P.). 



