110 MR. G. A. BOULBNGEE, ON THE AFRICAN AND [Feb. 7, 



B. Third anal spine longer than longest dorsal 

 spine. 



1. Head 2| to 3 times in total length ; D. XIII- 



XIV 10-13; A. Ill 7-9. 



a. Soft dorsal rays much shorter than head ; 



Sq. 32-34 ?tj 59. oUg acanthus Blkr. 



b. Middle soft dorsal rays produced, at least 



^_/« long as head. ^^^^^_ 



Sq. 32-34 ^j^^ 60. madagascariensis 



Sq. 35 r-^ &\. grandidieri^&n-v. 



2. Head 3^ times in total length ; D. XIV-XV 



12-13 ; A. Ill 10 ; middle soft dorsal and 



anal rays produced ; Sq. 31-33 r^ 62. betsileana Blgr. 



1, TiLAPIA HUNTERI. 



Oreochromis Jmnteri, Gunth. Proc. Zool. Soc. 1889, p. 70. 



Teeth very small, in 7 or 8 closely-set series in both jaws. 

 Depth of body equal to length of head, 31 times in total length. 

 Snout with concave upper profile, nearly twice diameter of eye, 

 which is 5 times in length of head and twice in interorbital width ; 

 mouth rather large, nearly | width of head ; maxillary extending 

 to between nostril and eye; 3 series of scales on the cheek. 

 Dorsal XVII 11 ; last spine longest, g length of head, | longest 

 soft rays. Pectoral pointed, a little shorter than the head, not 

 extending to origin of anal. Ventral reaching vent. Anal IV 10 ; 

 fourth spine longest, a little shorter than last dorsal. Caudal 

 truncate. Caudal peduncle a little longer than deep. Scales 

 cycloid, 35 A ; lat. 1. p. Dark brown, tinged with rusty ; vertical 



fins and ventrals blackish. 

 Total length 300 millim. 

 Crater Lake, Kilimandjaro. 



2. TiLAPIA NIGRA. 



Oreochromis niger, Griinth. Proc. Zool. Soc. 1894, p. 89, pi. ix. 



Teeth very small, in 4 or 5 closely-set series in both jaws. 

 Depth of body 2^ to 2^ in total length, length of head 3 to 3^ 

 times. Snout with straight upper profile, nearly twice diameter 

 of eye, which is 5 to 5| times in length of head and 2 to 2^ in 

 interorbital width ; mouth rather large, | to | width of head ; 

 maxillary extending nearly to below anterior border of eye ; 2 or 

 3 series of scales on the cheek. Grill-rakers short, 17 on lower 

 part of anterior arch. Dorsal XVII 11-12; last spine longest, 

 not quite 5 length of head ; middle soft rays much produced, more 

 than twice as long as longest dorsal spine. Pectoral pointed, as 

 long as the head, not extending to origin of anal. Ventral 

 reaching anal. Anal IV 9 ; fourth spine longest, nearly as long 

 as last dorsal ; soft rays produced. Caudal truncate or slightly 



