108 



ClCHLIDyE. 



liead, extending to below anterior border of eye, or to between nostril 

 and eye ; teeth in 3 to 6 more or less regular series, outer largest, 20 

 (young) to 60 in upper jaw, and separated from the others by a rather 

 wide interspace ; 3 or 4 series of scales on the cheek, width of scaly 

 part equal to or greater than diameter of eye in adult. Gill-rakers 

 short, 8-11 on lower part of anterior arch. Dorsal XIV-XVI 10-13; 

 last spine longest, f to f length of head ; middle soft rays more or less 

 produced in adult, usually as long as head. Anul III 7-10 (usually 

 8-9); third spine usually shorter than longest dorsal. Pectoral as long 



Fiir. 126. 



Tilapia zillii, 

 L. Menzaleh (F. N.). 



as head or a little shorter, rarely slightly longer, rarely extending to 

 vertical of origin of anal. Ventral usually reaching vent or anal. 

 Caudal truncate or rounded-subtruncate, rounded in old specimens. 

 Caudal peduncle as long as deep or a little deeper than long. Scales 

 cycloid or very feebly denticulate, 28-33 j^; lateral lines j^. Dark 

 green, olive, or brown, usually with 6 to 8 more or less distinct dark 

 cross-bars, with or without a dark stripe along the middle of the side ; 

 a black opercular spot ; sometimes a dark vertical bar below the eye ; 

 vertical fins with dark markings, ^^hich often form oblique streaks on 



