TJLAPIA. 



163 



dorsal. Pectoral 1 to 1^ times as long as head, reaching vertical of 

 origin of anal or beyond (shorter in the young). Ventral reaching vent 

 or anal. Caudal truncate in the young, rounded in the adult. Caudal 

 peduncle deeper than long. Scales cycloid, 31-35 j^^; lateral lines 

 j-j^. Yellowish brown or grey to dark olive, or silvery, the scales often 



darker at the base, or lighter in the centre ; some specimens spotted all 

 over with black ; young with 8 or 9 more or less distinct dark bars on 

 the body and a dark spot just below the upper border of the caudal 

 peduncle ; these markings may persist in the adult ; a blackish 



Fig. 100. 



>.->-v,^'^>.> ■ 



Tilapia nilotica. 

 Cairo (F. N.). a. 



opercular spot ; dorsal and anal fins with blackish and whitish spots 

 forming oblique series, or with oblique dark streaks; caudal fin with 

 more or less distinct bars, variable in number. 

 Total length 460 millim. 



From Lake Galilee and the Jordan southwards to East Africa, the 

 Upper Congo, and Lake Tanganyika, westwards through tlie Chad 

 Basin to the Senegal and Niger. 

 1-2. Ad. L. Galilee. Canon Tristram (C). 



3-12. Ad. & hgr. L. Mareotis. L. Loat, Esq. {V.). 



m2 



