TILAPIA. 



25; 



83. TILAPIA LATERISTRIGA. 

 Chromis lateristriga, part., Giinth. Proc. Zool. Soc. 1864, p. 312. 



Depth of body 2| to 3 times in total length, length of head 3 to o\ 

 times. Head 2 to 2^ times as long as broad ; snout rounded, with 

 straight upper profile, as long as broad, as long as postocular part of 

 head ; eye 3 (young) to 4 times in length of head, 1 to 1 J times in 

 iuterorbital width, equal to prseorbital depth in adult ; snout moderate, 



Fig. 170. 



Tilapia lateristriga. 



L. Nyassa. 



-| to § width of head, extending to between nostril and eye ; teeth rather 

 small, in 3 to 5 series, 40 to 70 in outer series of upper jaw ; 3 or 4 

 series of scales on the cheek, width of scaly part equal to or a little less 

 than diameter of eye. Gill-rakers rather short, 9 to 13 on lower part of 

 anterior arch. Dorsal XV-XVI 10-12 ; spines increasing in length to 

 the last, which is f to J length of head ; longest soft rays 5 to § length 

 of head in females, produced and as long as head in males. Anal 

 III 8-10 ; third spine J to f- length of head, Pectoral as long as or a 

 little longer than head, reaching or nearly reaching origin of anal. 

 Ventral reaching vent or anal. Caudal scaled, densely in large specimens, 

 feebly but distinctly emarginate 

 as long as deep. Scales very finely denticulate, 



Caudal peduncle 1^ to 1J times 



32-33 Y\ii3 ; lateral 



