TILAPIA. 197 



Scales not denticulate, 30-32 f^i^| ; lateral lines =^. Yellowish olive 

 above, whitish beneath; 8 or 9 dark brown cross-ban.ls on the head and 

 back, not descending to the belly, the first between the eyes ; fins olive, 

 dorsal and anal with yellowish spots at the base ; a dark basal spot at 

 the origin of the soft dorsal. 



Total length 130 millim. 



Portuguese Guinea. 



1-6. Types. Geba R. at Bafatii. Dr. W. J. Ansorge (C). 



7-0. Ad. Culiifi R. above Bafata. 



3-i. TILAPIA ZILLII. 



Aceriiia zillii, Gerv. Ann. Sc. Nat. (3) x. 1848, p. 203. 



Coptodon zillii, Gerv. Bull. Soc. Agric. Heranlt, 1853, p. 80, pi. iv. figs. 5-7 ; 



A. Dum. Arch. Miis. x. 1850, p. 252. 

 Glypldsodon zillii, Val. C.H. Ac. Se. xlvi. 1858, p. 713. 

 Haligenes tristrami, Glintli. Proc. Zool. Soc. 1859, p. 471, pi. ix. fio-. B. 

 Chromis tiistrami, part., Giiuth. Cat. Fish. iv. p. 20!) (18G2). 

 Sarotherodon? zillii, Giinth. t. c. p. 274. 

 Chromis andrece, Giinth. Proc. Zool. Soc. 1864, p. 492 ; Lortet, Ann. Mus. Lyon, 



iii. 1883, p. 142, pi. viii. fig. 3; Tristr. Faun. Palest, pi. xvii. fig. 1 



(1884). 

 Chromis niloticus, part., Gerv. Zool. Pal. Gen. p. 205, pi. xlv. fig. 3 (1869), and 



Journ. de Zoo), iii. 1874, p. 455. 

 Chromis mossamhicus, part., SteinJ. Sitzb. Ak. Wien, Ix. i. 1870, p. 2;!. 

 Chromis zillii, Sauv. Bull. Soc. Philom. (7) i. 1877, p. 163 ; Holland, Rev. 



Scientif. (4) ii. 1894, p. 418, fig. 

 Chromis inenzalensis, J. C. Mitch. Rep. Fish. L. Menzalch, p. 13, pi. iii. (1895). 

 Chromis tristrami, Giinth. Proc. Zool. Soc. 1896, p. 218. 

 Tilapia tristrami, Bouleng. Tr. Zool. Soc. xv. 1898, p. 6. 

 'J'ihipia menzalensis, Bouleng. Proc. Zool. Soc. 1899, p. 119. 

 Tilapia zillii, Bouleng. 1. c. ; Pellegr. Mem. Soc. Zool. France, xvi. 1904, p. 327 ; 



Bouleng. Fish. Nile, p. 519, pi. xcii. (1907). 

 Chromis busumanus, Giinth. Proc. Zool. Soc. 1902, ii. p. 333, pi. xxx. 

 Tilapia husujnana, Peilegr. t. c. p. 332. 



Depth of body 2-g- to 2|- times in total length, length of head 2f to 3^ 

 times. Head If to 2 times as long as broad ; snout with straight or 

 slightly concave upper profile, a little broader than long, as long as or a 

 little shorter than postorbital part of head ; eye 3^ (young) to 5 times 

 in length of head, 1 (young) to 2 times in interorbital width, less than 

 priEorbital depth in adult; mouth usually rather large, f to f width of 



