BAYONIA.— HEMITILAPIA. 489 



of head. Pectoral as long as head, reaching vertical of origin of anal. 

 Ventral reaching origin of anal. Caudal truncate. Caudal peduncle 

 a little longer than deep. Scales feebly denticulate, 32 jj ; lateral 

 lines ^-]3- Brownish above, whitish beneath, with eight darker cross-bars, 

 traversed by a dark lateral stripe extending from the opercular spot to 

 the caudal; vertical fins uniform brownish, paired fins whitish. 



Total length 90 millim. 



Victoria Nile (Ripon Falls). — Type in Genoa Museum. 



31. HEMITILAPIA. 

 Bouleng. Ann. & Mag. N. H. (7) x. 1902, p. 70. 



Body moderately elongate ; scales ctenoid ; two incomplete lateral 

 lines. Jaws with moderately broad bands of slender, club-shaped, 

 movable teeth, with slightly incurved crowns, those of the outer series 

 larger, with the crown obliquely truncate and pointing towards the 

 symphysis. Maxillary exposed at the end. Dorsal with 15 or 16 spines, 

 anal with 3. Occipital and parietal crests strong, extending to between 

 the orbits. Vertebrae 31 (14-15 + 16-17). 



Lakes Nyassa and Victoria. 



Synopsis of the Species. 



Snout pointed, with straight or concave upper 

 profile ; pectoral a little shorter than 

 head ; caudal peduncle a little longer 



than deep ; Sc. 31-30 '-jr 1. II. oxyrliynchis, Blgr., p. 489. 



Snout obtuse, with straight upper profile ; 



pectoral as long as head ; caudal peduncle 



1\ times as long as deep ; Sc. 31- 



32 jj^ 2. H. bayoni, Blgr., p. 491. 



Snout obtuse, with convex upper profile ; 



pectoral at least as long as head ; caudal 



peduncle not or but slightly longer than [p. 492. 



deep ; Sc. 31-33 jr—p 3. II. materfamilias, Pellegr., 



1. HEMITILAPIA OXYRHYNCHUS. 



Bouleng. Ann. & Mag. N. H. (7) x. 1902, p. 71. 



Tilapia o.ryrhynchus, Pellegr. Mem. Soc. Zool. France, xvi. 1904, p. 334. 



Depth of body 2^ to 2| times in total length, length of head 3 times. 

 Head 2\ to 21 times as long as broad, with concave upper profile ; snout 



