TILAPIA. 197 



Scales not denticulate, 30-32 Yi~il '■> lateral lines jj^f|. Yellowish olive 

 above, whitish beneath; 8 or 9 dark brown cross-bands 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 Batata. Dr. W. J. Ansorge (( '. I. 



7-9. Ad. (,'ulufi R. above Batata. 



34. TILAPIA ZILLII. 



Acerina zillii, Gerv. Ann. Sc. Nat. (3) x. 1818. p. 20.3. 



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



A. Dam. Arch. Mus. x. 1859, p. 252. 

 Glyphisodon zillii, Val. C.R. Ac. Sc. xlvi. 1858, p. 713. 

 Haligenes tristrami, Giintli. Proc. Zool. Soc. 1859, p. 471, pi. ix. fig. B. 

 Chromis tristrami, part,, Giiuth. Cat. Fish. iv. p. 26',) (1862). 

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

 Chromis andrete, 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 Zool. iii. 1874, p. 455. 

 Chromis mossambicus, part., Steiiul. Sitzb. Ak. Wien, lx. i. 1870, p. 23. 

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



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

 Chromis menzalensis, J. C. Mitch. Rep. Fish. L. Menzalcli, p. 13, pi. iii. (1895J. 

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

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

 Tilapia menzalensis, Bouleng. Proc. Zool. Soc. 1899, p. 119. 

 Tilapia zillii, Bouleng. 1. c. ; Pellegr. Mem. Soc. Zool. Fiance, xvi. 1901, p. 327 ; 



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

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

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



Depth of body 2£ to 2f times in total length, length of head 2f to 3 J 

 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 

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



