138 CICHLTD.E. 



Teeth in a single series, 14-20 in upper jaw, 



grooved in front; dorsal with 18-20 spines. 40. Plecodus, Blgr., p. 503. 



II. Dorsal and anal fins with a scaly sheath at the base. 

 Teeth with blunt crowns, in a single series, two 

 or four middle ones enlarged ; dorsal with 

 lG-20 spines, anal with 8-10 .... 41. Paretroplus, Blkr., p. 504. 



1. TILAPIA. 



Chromis, part., Cuvier, R^gne Anim. ii. p. 2GG (1817) ; Giinth. Oat. Fish. iv. 



p. 2G7 (18G2). 

 Tilapia, A. Smith, 111. Zool. S. Afr., Fish. (1840) ; Bouleng. Proc. Zool. Soc. 



1899, p. 105, part., and Poiss. Bass. Congo, p. 452 (1901) ; Pellegr. Mem. 



Soc. Zool. France, xvi. 1904, p. 307 ; Bouleng. Fish. Nile, p. 513 (1907). 

 Sarotherodon, Riipp. Verz. Mus. Senck. iv. p. 21 (1852) ; Giinth. Cat. iv. p. 273. 

 Coptodon, Gervais, Bull. Soc. Agric. Herault, 1853, p. 81. 

 JTaligenes, Giinth. Proc. Zool. Soc. 1859, p. 471. 



Ptycliochromis, Steind. Sitzb. Ak. Wien, Ixxxii. i. 1880,'p. 248; Pellegr. t. c. p. 34C. 

 Oreochromis, Giinth. Proc. Zool. Soc. 1889, p. 70 ; Pellegr. t. c. p. 354. 

 Ctenochromis, part., Pfeff. Jahrb. Hamb. Wiss. Anst. x. 1893, p. 149. 

 Oplithalmotilapia, Pellegr. t. c. p. 345. 



Body short or more or less elongate ; scales cycloid or ctenoid ; two 

 incomplete lateral lines. Teeth in 2 or more series, the outer bicuspid *, 

 the others tricuspid; maxillary usually more or less completely hidden 

 under the prseorbital when the mouth is closed f. Dorsal fin with 11 

 to 19 spines, anal with 3 or 4. Parietal and occipital crests strong, 

 extending to between the orbits. Vertebrae 26-34 %. 



Africa and Syria. 



* Occasionally conical or indistinctly bicuspid in a few species which are related to 

 T. nilolica (T. nigra, mossamhica, naUdensis, linnelli, sqicamipinnis). See also Ilaplochromis. 

 t Exceptions in T. bueitil-oferi, fasciata, burtoni, acuticeps, swynnertoni, lucullce, horii. 

 t Numbers of vertebrre in species with cycloid scales :^ 

 14 + 12^26. 1'. macrocephcda, 



14 + 15=29. T.perdvali. 



15 + 13=28. T. dolloi, melanoplewa, cabrce, sparrmani. 



16 + 12=28. 2\ eduardiaiia, heudeloti, marue, zillii, buettikoferi. 

 16 + 13 = 29. T. melanopjleura, zillii, brevimanus. 



16 + 14=:30. T. shirana, natalensis. 

 17+13=30. 7'. r/alilcea, andersonii. 



17 + 15=32. 2'. niloiica, rjalihra. 

 17 + 10^33. T. ifrjiiamipitinis. 



