200 
THE TANGANYIKA PROBLEM. 
yellow, spotted with dark brown ; pectoral yellow ; branch iostegal membrane, 
pectoral region, outer edge of ventrals, and anal vermilion-red. 
Total length, 120 millim. 
Two specimens of this handsomely coloured fish, which bears the native name 
“ Kasanga Malengi,” on M. Dardenne’s coloured sketch. 
71. Tilapia dardennii. — Blgr. 1899. (Fig. facing p. 200.) 
Teeth very small, in 4 or 5 series in both jaws, outer bicuspid, separated from 
the series of smaller tricuspid teeth by a rather wide interspace. Depth of body 
3 to 3$ times in total length, length of head 3J to 3.C Snout, with strongly curved 
upper profile, little longer than the diameter of the eye, which is 3I times in 
length of head and equal to or a little less than interorbital width ; mouth small, £ 
Tilapia pleurotaenia. See p. 202. 
width of head, extending to between nostril and eye ; 5 or 6 series of scales on 
cheek ; large scales on the opercle. Gill-rakers short and thick, 13 on lower 
part of anterior arch. Dorsal XIX. 10 ; sixth to ninth spines longest, not quite half 
length of head, a little shorter than longest soft rays. Pectoral acutely pointed, as 
long as or slightly shorter than the head, not extending to origin of anal. Ventral 
reaching vent, or not quite so far. Anal III. 8; third spine as long as and 
much stronger than longest dorsals. Caudal feebly emarginate. Caudal peduncle 
if, or ij as long as deep. Scales, mostly ctenoid, 37 ~ ; lat. 1. ^ 2 \ Yellowish 
olive above, silvery beneath, with 10 or 11 dark dorsal cross-bars, the first between 
the eyes ; yellowish streaks along the series of scales ; fins yellowish, dorsal with 
some olive marblings, pectoral and anal red at the base. 
Total length, 155 millim. 
Described from two specimens Native name, “ Sangani.” 
