SYXODOIS'TIS. 



473 



Synodontis melanogaster, Ehrenb. in Peters, Keise n. Mossanib. iv. p. 31 (18G8). 

 Synodontis membranacnis, Vaill. N. Arch. Mus. (3) viii. 1896, pp. 161 & 167. 



Depth of body 2f to 3 times in total length, length of head 2| to 3J 

 times. Head 1^ to If times as long as broad, rugose, granulate above 

 from between the eyes, the granulate area sometimes extending a little 

 on the snout ; snout obtusely pointed, as long as or a little longer than 

 postocular part of head ; eye supero-lateral, oj (young) to 5J times in 

 length of head, not less than interorbital width in young, 1 J to If times 



Fig. 354. 



Synodontis batensoda. 

 Mouth of L. No (F. N.). a. 



in interorbital width in adult ; operculum terminating in a few short 

 spines. Lips moderately developed ; praemaxillary teeth forming a short 

 and broad band ; movable mandibular teeth 4 to ^ diameter of eye, 30 

 to 57 in number. Maxillary barbel with a broad marginal membrane, 

 |- to about once length of head, usually reaching base of pectoral spine 

 or a little beyond ; mandibular barbels inserted on a straight transverse 

 line, the outer with long, slender, simple branches, 1^ to 2 times as long 

 as inner, some of the branches of which are bifid or trifid. Gill-openings 

 extending downwards beyond base of pectoral fin, but separated by a 

 broad isthmus, which at least equals interorbital width. Occipito-nuch;il 



