2 o6 THE TANGANYIKA PROBLEM. 



tricuspid, in 3 rows ; 2 or 3 series of scales on the cheek ; large scales on the 

 opercle. Gill-rakers short, 13 on lower portion of anterior arch. Dorsal XII. -XIII. 

 14 ; spines slender, equal from the seventh, which measures nearly \ length of head ; 

 soft rays scarcely longer. Pectoral pointed, as long as head, reaching origin 

 of anal. Ventral produced into a filament, extending beyond origin of anal. Anal 

 III. S-9 ; third spine as long as and stronger than longest dorsal spines. Caudal 

 deeply emarginate, crescentic. Caudal peduncle nearly twice as long as deep. 



Scales thin, without denticulation, 39-40 — — - ; lat. I - — — . Brown above, 



1 4 — ! 5 1 5 — 19 



white beneath ; a blackish opercular spot. 



Total length, 90 millim. 



Described from two specimens from Msambu. 



76. Tilapia grandoculis. — Blgr. 1899. (Fig. p. 193. Lower.) 



Teeth very small, in 4 or 5 series in both jaws, of outer series larger, bi- or 

 tricuspid, and very obtuse. Depth of body 3! times in total length, length of head 3. 

 Snout short, with rounded upper profile ; eye very large, a little longer than the 

 snout, its diameter 2.} in length of head, and slightly greater than the interorbital 

 width ; mouth small, i width of head, extending to between nostril and eye ; a few 

 deciduous scales on the cheek ; larger scales on the opercle. Gill-rakers very short, 

 rather thick, 17 on lower part of anterior arch. Dorsal XIII. 14 ; spines slender, 

 equal in length from seventh, measuring I length of head, and a little shorter than 

 longest soft rays. Pectoral falciform, slightly longer than the head, extending as 

 far as origin of anal. Ventral prolonged in a long filament extending beyond 

 origin of anal. Anal III. 10 ; third spine shorter but stronger than longest 

 dorsals. Caudal with deep crescentic notch. Caudal peduncle a little longer than 



deep. Scales mostly ctenoid, 63— ; lat. 1 -,. Brown above, with ill-defined 



F ^25 32—36 



darker spots, whitish beneath ; pectorals yellowish ; other fins blackish towards the 



edge. 



Total length, 115 millim. 



Described from a single specimen. 



77. Tilapia microlepis. — Blgr. 1899. (Fig. facing p. 204.) 



Teeth very small, in 4 series close together in both jaws, outer larger, biscupid, 

 with a principal and a small lateral cusp. Depth of body 3§ to 4 times in total 

 length, length of head 3. Snout, with straight or slightly convex upper profile, ii 

 the diameter of the eye, which is nearly 4 times in length of head and equals inter- 

 orbital width ; mouth moderate, its width | that of the head, extending to between 

 nostril and eye ; 7 or 8 rows of scales on the cheek ; larger scales on the 

 opercle. Gill-rakers short, rather thick, 13 or 14 on lower part of anterior arch. 

 Dorsal XVI. -XVII. 14-15 ; spines sub-equal in length from the fifth or sixth, 

 measuring 1^ length of head and a little shorter than longest soft rays. Pectoral 

 acutely pointed, -| length of head, not extending to origin of anal. Ventral widely 

 separated from vent. Anal III. 9 ; third spine as long as and a little stronger than 



