1899.] SYEIAN FISHES OF THE FAMILY CICHLIDA-. 119 



19. TiLAPIA OYALIS. 



Ohromis ovalis, Steiad. Verb, zool.-bot. Ges. Wien, xvi. 1866, 

 p. 761. 



Allied to T. zillii. Depth of body ecjual to length of head, 3 

 times in total length. Suoiit with straight upper profile ; diameter 

 of eye 4 times in length of head, a httle less than interorbital 

 width ; maxillary extending a little beyond vertical of anterior 

 border of eye; 3 series of scales on the cheek. Dorsal XIV 11 ; 

 last spine longest ; middle soft rays produced. Pectoral shorter 

 than the head. A^entral extending a little beyond origin of anal. 

 Anal III 8. Caudal rounded. Scales 29^^ ; lat. 1. ||. OHve- 



brown, with indistinct darker bars ; a black opercular spot ; dorsal 

 and anal with black streaks ; a black spot on the anterior soft rays 

 of the dorsal. 



Total length 100 millim. 



Angola. 



20. TlLAPIA MENZALENSIS. 



Chromis menzalensis, Mitchell, Eep. Fish. L. Menzaleh, p. 13, 

 pL iii. (1895). 



Teeth in 4 or 5 series in both jaws, outer rather large. Depth 

 of body 2| in total length, length of head 3 times. Snout with 

 straight or slightly concave upper profile, Ij to 2 diameter of eye, 

 which is 4 to 5 times in length of head and Ij to 2 in interorbital 

 width ; mouth large, | to 4 width of head ; maxillary extending to 

 below anterior border of eye ; 3 or 4 series of scales on the cheek ; 

 large scales on the opercle. Gill-rakers short, 9 or 10 on lower 

 part of anterior arch. Dorsal XV 12-13 ; last spine longest, 

 f to 5 length of head ; middle soft rays produced in adult speci- 

 mens, about twice as long as last spine. Pectoral pointed, as long 

 as the head or a little shorter, not extending to origin of anal. 

 Ventral produced in the adult, reaching anal. Anal III 8-9; 

 third spine shorter than longest dorsal, soft rays produced like 

 the dorsals. Caudal truncate, rounded in old specimens. Caudal 

 peduncle as long as deep. Scales cycloid, 30-31— ; lat. 1. |^. 

 Olive, with 7 or 8 dark bars, sometimes with a dark stripe along 

 the middle of the side ; ventrals and vertical fins dark, the latter 

 sometimes with ill-defined lighter spots ; a more or less distinct 

 round black spot between the anterior soft rays of the dorsal ; a 

 black opercular spot. 



Total length 235 millim. 



Lake Menzaleh, Lower Egypt. 



21. TiLAPIA ZILLII. 



Acerina zillii, Q-ervais, Ann. Sc. Nat, (3) x. 1848, p. 203, 

 Coptoclon zillii, Gervais, Bull. Soc. Agric. Herault, 1853, p. 80, 

 pi. iv. figs. 5-7 ; A. Dum. Arch. Mus. x. 1859, p. 252. 

 Olyphisodon zillii, Valenc. C.E. Ac, Sc, xlvi. 1858, p. 713. 



