118 MR. G. A. BOULESTGER ON THE AFEICAN AND [Feb. 7, 



16. TiLAPIA PLEUROMELAS. 



Tilapia 2:>leuromelas, A. Dum. Arch. Mus. x. 1859, p. 253. 



Tilapia lateralis, A. Dum. 1. c. 



Chromis pUuromelas, Griinth. Cat. iv. p. 271 (1862). 



Chroinia lateralis, Giinth. t. c. p. 272. 



Depth of body about tw ice in total length. 2 series of scales on 

 the clieek. 15-17 gill-rakers on lower part of anterior arch. 

 Dorsal XIV 12-14. Anal III 10. Caudal rounded. Scales 



cycloid, 26-29 ^. Brow^n ; a large black blotch on each side of 

 the body. 



Total length 200 millim. 



Senegal. 



17. TiLAPlA HETJDELOTI. 



Tila2na heuddotii, A. Dum. Arch. Mus. x. 1850, p. 254. 



Chromis heudelotii, Giinth. Cat. iv. p. 270 (1862). 



Depth of body a little moi-e than twice in total length. 3 series 

 of scales on the cheek. 16 gill-rakers on lo\^er part of anterior 

 arch. Dorsal XIV 10. Anal III 7. Caudal rounded (?). 

 Scales cycloid, 27 ^. Brownish ; soft dorsal « itli irregular light 

 and dark streaks. 



Total length 120 millim. 



Senegal. 



18. Tilapia sparrmani. 



Tilajna sparrmanii. Smith, 111. Zool. S. Afr., Fish. pi. v. (1840). 



Chromis sparmanni, Giinth. Cat. It. p. 269 (1862). 



Chromis niloticus, part., Peters, Keise n.Mossamb. iv. p. 23 (1868). 



Teeth very small, in 3 to 5 series in both jaws. Depth of body 

 2| to 2f times in total length, length of head 3 to 3^. Snout 

 with straight or slightly convex upper profile, as long as the eye, 

 which is 3^ to 4 times in length of head and 1^ to If in inter- 

 orbital width ; mouth moderate, f width of head ; maxillary 

 extending to below anterior border of eye ; 2 series of scales on 

 the cheek ; large scales on the opercle. Gill-rakers very short, 

 10 to 12 on lower part of anterior arch. Dorsal XIII-XV 9-11 ; 

 last spine longest, f to | length of head, | to | longest soft rays. 

 Pectoral pointed, a little shorter than the head, not extending to 

 origin of anal. Ventral reaching origin of anal. Anal III 9 ; 

 third spine a little shorter but stronger than last dorsal spine. 

 Caudal rounded. Caudal peduncle as long as deep. Scales cycloid, 

 27-29 f}^ ; lat. 1. ^^. Pinkish to brownish, with 7 or 8 rather 

 indistinct dark brov\n or olive bars ; vertical fins with some small 

 dark spots ; a large blackish spot on the dorsal, between the anterior 

 soft rays ; a dark opercular spot. 



Total length 145 millim. 



South-west Africa, from Angola and the Victoria Falls to 

 Namaqualand. 



