TILAP1A. 513 



6. TILAPIA. 



A. Smith, UJ. Zool. S. Afr., Fish. (1840) ; Boulenger, Proc. Zool. Soc. 1899, p. 105, part., and 

 Poiss. Bass. Congo, p. 452 (1901) ; Pellegrin, Mem. Soc. Zool. France, xvi. 1904, 

 p. 307. 



Sar other odon, Biippell, Verz. Mus. Senckenb. iv. p. 21 (1852) ; Giinther, Cat. Fish. iv. p. 273 

 (1862). 



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



Haligenes, Giinther, Proc. Zool. Soc. 1859, p. 471. 



Chromis, Giinther, Cat. Fish. iv. p. 267. 



Oreochrornis, Giinther, Proc. Zool. Soc. 1889, p. 70 ; Pellegrin, t. c. p. 354. 



Teeth in three or more series, the outer bicuspid, the inner tricuspid. Maxillary 

 bone entirely concealed under the prseorbital when the mouth is closed, or a very small 

 portion of its distal extremity exposed. Body short or moderately elongate ; scales 

 cycloid, or ctenoid; two lateral lines. Dorsal fin with 13 to 19 spines, anal with 3 or 4. 

 Vertebra 28 to 32 (14-17 + 13-15). 



Africa and Syria. 



A large genus, including about seventy species, eight of which are here described. 



Synopsis of the Species. 



I. 7 to 10 gill-rakers on lower part of anterior arch ; three to five series of scales on the cheek ; 

 pectoral fin not longer than head. 



A. Caudal peduncle once and one-fourth to twice as long as deep ; mouth extending usually 



to below anterior border of eye, or beyond ; D. XV-XVI 8-10 ; scales denticulate. 



Diameter of eye twice and two-thirds to three times in length of head, 

 greater than length of snout or interorbital width ; four or five 

 series of scales on the cheek ; caudal fin truncate 1. T. martini, Blgr. 



Diameter of eye three and one-third to three and a half times in length 

 of head, equal to length of snout or interorbital width ; three or four 

 series of scales on the cheek ; caudal fin truncate 2. T. laerimosa, Blgr. 



Diameter of eye three to three and a half times in length of head ; three 



or four series of scales on the cheek ; caudal fin rounded .... 3. T. nubila, Blgr. 



B. Caudal peduncle not or but slightly longer than deep ; D. XIV-XVI 9-13. 

 Diameter of eye three and one-fourth times in length of head, greater 



than length of snout ; scales denticulate 4. T. nigricans, Blgr. 



Diameter of eye three and a half to five times in length of head, 

 not greater than length of snout ; scales not or but very feebly 

 denticulate 5. 1\ zillii, Gerv. 



3u 



