154 
THE TANGANYIKA PROBLEM. 
POLYPTERID/E. 
1. P. Congicus. — Blgr. 1898. (Fig., p. 153, lower). 
LEPIDOSIRENIELE. 
2. Protopterus /ETHiOPicus. — Heck 1851. (Fig., p. 153, upper). 
CHAR AC I N IILE. 
3. Hydrocyon lineatus. — Blkr. 1863. 
4. Alestes macrophthalmus. — G thr. 1867. 
When this species was first recorded from Lake Tanganyika, it was only known 
from the Gaboon. It has since been found in Lake Mweru and in the Congo. 
5. Alestes macrolepidotus. — C. and V. 1849. 
Kalambo. 
6. ClTHARINUS GIBBOSUS. — Blgr. 1 899. (Fig., p. 155.) 
Kalambo. The largest specimen measures 500 millim. 
CYPRINIDzE. 
7. Capoeta tanganic/E. — Blgr. 1900. (Fig., p. 163.) 
Depth of body 3I to 4 times in total length, length of head 5 times. Snout broad 
and rounded, as long as or slightly longer than the eye, the diameter of which is 
3.} times in the length of the head and nearly twice in the interocular width ; the 
width of the mouth equals § that of the head ; a minute barbel, hidden under the 
lip at the angle of the mouth. Dorsal III. 9; third ray very strong, ossified, 
smooth ; the fin, which is equally distant from the eye and from the caudal, has the 
free edge notched, and its greatest depth equals the length of the head. Anal III. 
5 ; the longest ray measures \ the length of the head. Pectoral acutely pointed, as 
long as the head, not reaching the ventral, which is inserted under the first rays of 
the dorsal. Caudal forked. Caudal peduncle twice as long as deep. Scales 
68-70 — 14 , 9 or 10 between the lateral line and the root of the ventral. 
14—15 
Olive above, each scale darker at the base, silvery white beneath ; fins greyish. 
Total length, 320 millim. 
Described from three specimens from the north end of Lake Tanganyika. 
The discovery of a species of this genus in Lake Tanganyika is particularly 
interesting from the fact that only one was known from Africa, viz., the Abysin- 
nian C. dilloni , C. and V. ; this is distinguished by the absence of barbels and the 
greater size of the scales (30 to 32 in the lateral line). In the presence of a pair of 
barbels and the small size of the scales, C. langanica belongs to the typical section 
of the genus, inhabiting south-western Asia ; but it has the enlarged dorsal ray 
neither feeble, as in C. fundulus , Pall, and allied species, nor serrated, as in 
C. truita, Heck. 
